Occasionally the General Social Survey, which annually takes the pulse of America for the past four decades, has asked its random sample of several thousand people if they agree with this somewhat depressing question: “In my opinion, life does not serve any purpose.”

The survey has also asked respondents about their belief and concept of God. And a researcher at the University of Pennsylvania recently examined responses to the two questions and found those who hold a firm belief in God stand out from all others for their having a higher sense of purpose.

Even those who believed in an abstract higher power statistically had more in common with doubters and nonbelievers when it came to having a higher sense of purpose in life, according to an article published in the most recent issue of the Journal for the Scientific Study of Religion.

"That surprised me," said Stephen Cranney, author of the article and doctoral candidate at Penn's Population Studies Center. "I thought logically if there is an effect, there would be a gradient that led from nonbelief to you believe a little bit to you are firm about your belief. But what's actually the case is there isn't any kind of association until you are in the firm believer category."

The findings corroborate a large body of research that ties religiosity and spirituality with good health and psychological well-being.

Studies have found that one of the basic measures of religiosity — worship service attendance — boosted the immune system, decreased blood pressure and may add as much as two to three years to your life, a Stanford University anthropologist recently wrote.

But a survey by Baylor University found that measures of religiosity had little effect on one's mental health. Instead, researchers found that people who believed in a judgmental God had higher levels of anxiety, paranoia and compulsion than those who believed in a caring, engaged God who would help them cope.

"When it comes to mental health, the aspect of religion that matters the most is the nature of one’s relationship with God," the 2010 Baylor Religion Survey concluded.

More recent research out of Harvard University suggests belief in God may significantly improve the outcome of those receiving short-term treatment for psychiatric illness, according to PsychCentral.

“Belief was associated with not only improved psychological well-being, but decreases in depression and intention to self-harm,” David H. Rosmarin, an instructor in the Department of Psychiatry at Harvard Medical School, told the publication.

The sample for that study included 159 people, and most of the research that has explored religious influences on sense of purpose has been based on a few hundred people — but Cranney's use of the GSS gave him a large random sample of more than 2,000.

"In brief, this study is the first of its kind to measure the relationship between several categories of belief in God and sense of purpose, and it has the sample size to do so effectively," Cranney wrote.

The 1998 and 2008 General Social Surveys measured participants' responses on a scale from "strongly agree" to "strongly disagree" that life serves no purpose. Cranney noted that just .8 percent of people said they strongly agreed, confirming the fact that most people have a strong urge to find purpose in their lives.

He then compared those responses to questions that gauged someone's belief in God, ranging from "no belief" to "believes-doubts" to "higher power" to "believes-sure."

Cranney writes that believers in a higher power and believing doubters have a significantly different sense of purpose from sure believers, and that this finding supports other research that has found belief systems that “embrace uncertainty and ambiguity” also invite potential "existential uncertainty."

But Cranney doesn't venture into what his findings mean.

He writes that people with a higher sense of purpose may be naturally drawn toward belief, while others may derive their sense of purpose from secular alternatives.

Cranney said more information gathered through qualitative interviews that flesh out what people mean by their belief in God and their sense of purpose is needed to better understand the relationship.

Matt is an enterprise team editor. Before, he wrote about faith how it is lived, how it intersects with society and how current trends affect religious practice. He has worked for more than 12 years as an editor, most more ..